In a Kruskal-Wallis test, there are four samples and the value of the test statistic is calculated as H = 8.79. The most accurate statement that can be made about the p-value is that:
A) it is greater than 0.10
B) it is greater than 0.05 but smaller than 0.10
C) it is greater than 0.05
D) it is greater than 0.025 but smaller than 0.05
E) it is less than 0.025

Question

Quizplus · Accepted Answer

To determine the p-value, we need to compare the test statistic (H = 8.79) to the critical value from the chi-squared distribution with degrees of freedom equal to the number of samples minus 1 (k-1). Assuming a significance level of 0.05, for a four-sample Kruskal-Wallis test, the critical value is 9.49. Since the test statistic (H = 8.79) is less than the critical value (9.49), we fail to reject the null hypothesis and conclude that there is insufficient evidence to suggest that the medians of the four samples differ. However, since the test statistic is relatively close to the critical value, the p-value is likely to be small but greater than 0.025. Therefore, the most accurate statement is that the p-value is greater than 0.025 but smaller than 0.05, which corresponds to choice D.

In a Kruskal-Wallis Test, There Are Four Samples and the Value